Basics

Question 1

When escaping quotes what symbol is used and where does it go?

E.g.
‘The man said, ‘Hi there!’’

Answer 1

Input backslash () BEFORE the character you want to escape

# with single quotes and escaping
'The man said, \'Hi there!\''

Question 2

When would you make a ruby symbol?

how do you make a ruby symbol?

Answer 2

when you want to reference something like a string but don’t ever intend to print it to the screen or change it.

:variable_name

Question 3

what method checks if something is a nil or not?

Answer 3

.nil?

E.g.
“Hello, World”.nil?
=> false

Question 4

when nil is used in an if statement, what is nil treated as?

E.g.
if nil
…
end

Answer 4

false

Question 5

is false the same as nil?

Answer 5

no. they are not equivalent

false == nil
=> false

Question 6

what is the modulo operator?

Is it the same a division?

Answer 6

%

No. It returns the remainder of a division operation

Question 7

what happens when you try to divide integers that don’t divide evenly?

15 / 4

Answer 7

an integer is returned

15 / 4
=> 3

Question 8

how would you get a more accurate calculation of this division problem?

15 / 4

Answer 8

use floats

15.0 / 4
=> 3.75

Question 9

can use the == operator be used to compare strings?

Answer 9

yes

‘foo’ == ‘foo’
=> true

‘foo’ == ‘bar’
=> false

Question 10

what operator is used in String Concatenation?

Answer 10

the + operator

‘foo’ + ‘bar’
=> “foobar”

Question 11

what is this called?

=>

Answer 11

a hash rocket

Question 12

what is a ruby expression?

Answer 12

anything that can be evaluated

Pretty much everything you write in Ruby is an expression.

An expression in Ruby always returns something, even
if that’s an error message or nil

Expressions do something, but they also return something.

Question 13

when do you define a constant variable?

Answer 13

When you want to represent a value that will not change in your Ruby program